1. Field of the Invention
The present invention relates to a brake controller that controls the braking force applied to the wheel of a vehicle.
2. Description of the Related Art
A conventional electronically controlled brake control system for a vehicle (for example, in Japanese Patent Application Publication No. 62-18359 (1987)) generates a deceleration error signal by comparing the driver braking request signal with the measured deceleration. This brake system further has a means for correcting the braking request signal that generates an adaptive coefficient from the deceleration error signal and corrects the braking request signal by using an adaptive coefficient under prescribed conditions, such as vehicle speed, brake level, and operating inclination, of over a plurality of stoppings of the vehicle. The brake system compensates for brake deterioration over an extended period of time and restores desired brake performance.
However, the measured deceleration error may vary in response to factors other than brake deterioration, such as the variations in the vehicle operating conditions, for example, the environmental temperature, external disturbances and the occurrence of abnormalities. Because of this, the adaptive coefficients obtained from the deceleration level error signal may be difficult to appropriately characterize as reflecting (resulting from) only the deterioration of the brake over an extended period of time. In such a case, the use of an adaptive coefficient does not necessarily compensate for long-term brake deterioration and stabilization of the braking effectiveness.